What makes me think it's at least plausible is that there are no obvious fringes around the kid's hair - cutting and pasting hair is always interesting in Photoshop - and the light looks believable. Often when you try to montage two scenes they're lit from completely different angles, and which doesn't seem to be true here.
Then again you're right about the splashes, and the aim is possibly a little too perfect.
So I'd say it's open - could be either.
The sheer accuracy of hitting the centre of the helmet is a bit dubious though I agree Any idiot can face a crisis - it's day to day living that wears you out.
